Icemaker

ABSTRACT

Disclosed is an icemaker. The icemaker in accordance with one embodiment of the present invention comprises: an ice tray; at least one heater housing portion which is formed on the ice tray; and a heater, which is provided with a soft external cover or an external cover having elastic force and is housed inside the heater accommodation portion while being in close contact with the heater accommodation portion, for heating the ice tray.

TECHNICAL FIELD

The present invention relates to an ice maker, and more particularly, to an ice maker provided with a heater which serves ice to be easily separated from an ice tray.

BACKGROUND ART

In general, a refrigerator is used to store foods for a long time so as not to spoil them, but recently it is a trend that a variety of functions have been added in addition to the storage of foods. Conventionally, a function of ice-making is one of the functions provided in the refrigerator, but an ice maker which generates ice automatically by automating an ice-making process and stores the generated ice in an ice bank is one of the items which improve the ease of use.

Such an ice maker may be classified as a twist method, an ejector method and a rotation method, depending on the method of ice-separation.

The twist method is a method that makes ice to drop by twisting an ice tray. The ejector method is a method that makes ice to draw up from the ice tray and then to drop by an ejector installed on the upper side of the ice tray. The rotation method is a method that makes ice to drop by rotating the ice tray.

Such types of ice makers may serve the entire size of the ice makers to be slimmed. Accordingly, the effective volume in a refrigerator may be expanded, and also the configuration of equipment may also be simplified. However, in case where the ice-separation from the ice tray is not fulfilled smoothly in such types of ice makers, the ice maker may not be operated efficiently.

In view of such a problem, it is disclosed an ice maker provided with a heater in Korean Patent Laid-Open Publication No. 2006-0009405. The disclosed ice maker is configured to be equipped with a heater for ice-separation to apply heat to the ice tray.

It is disclosed an ice maker for a refrigerator in Korean Patent Laid-Open Publication No. 2010-0138373. The disclosed ice maker includes a water supply unit which is installed on one side of an ice tray and supplies water to the ice tray; a lever for ice-separation which is assembled rotatably between a driving unit installed on one side of the ice tray and the water supply unit, and is rotated by a motor mounted in the driving unit; a heater for ice-separation which applies heat to the ice tray to separate ice from the ice tray; an inserting recess formed to be adjacent to the heater for ice-separation; a fitting recess formed on one side of the inserting recess; and a bimetal or a thermal fuse which is inserted into the inserting recess and cuts off the power to the heater for ice-separation at a predetermined temperature.

The ice maker as described above is configured to be equipped with a heater on the lower portion of the ice tray to provide a smooth ice-separation. The heater is configured to have a hot wire installed inside the metal tube. The heater is also configured in a way that the heater is installed in a lead-in recess formed on the lower portion of the ice tray and is supported by a jaw formed on the end side within the lead-in recess.

Such the heater formed on the lower portion of the ice tray does not get in a contact with the ice tray smoothly, and thereby there is a problem that it takes a relatively longer time to heat the lower surface of the ice tray to a predetermined temperature. When the heater is operated for a longer time, the overall temperature of the ice-making chamber having the ice maker therein is increased. In this case, after the ice within the ice tray is separated and moved to the ice bank, when making ice again with the supplied ice-making water, it takes a longer time to cool the ice tray to the ice-making temperature.

Therefore, the total ice-making time required for completing a cycle of ice-making process becomes longer, and the power consumption required for the ice-making process becomes higher.

In addition, since the heater is installed in a state that the lower portion of the ice tray is exposed to the outside, the heat loss generated from the heater is relatively higher.

DISCLOSURE Technical Problem

In view of the above, in order to solve the above described problems, the present invention provides an ice maker which is capable of reducing a heat loss of a heater installed in the lower portion of an ice tray for ice-separation and capable of reducing a time required for heating the ice tray to a predetermined temperature of ice-separation by getting the heater in a close contact with the ice tray.

Further, the present invention provides an ice maker which is capable of fixing reliably a thermo limiter for preventing overheating when coupling to a base cover which is coupled to the ice tray.

TECHNICAL SOLUTION

An ice maker of the present invention to solve the above technical problem includes an ice tray;

at least one heater housing which is formed in the ice tray; a heater which is equipped with a soft or an elastic outer shell and is accommodated in a close contact within the heater housing, and heats the ice tray; and a base cover which is coupled to the ice tray, and is equipped with a support rib which pressurizes the heater mounted in the heater housing to make the heater getting a close contact with the heater housing.

ADVANTAGEOUS EFFECTS

An ice maker in accordance with the present invention is capable of widening an area where a heater gets in a direct contact with an ice tray, and is capable of forming the heater over the entire area of the ice tray, and thereby it is possible to reduce a time required for heating the ice tray to a predetermined temperature. Also, it is capable of reducing an increase of the overall temperature of an ice-making chamber having an ice maker therein, and thereby when ice is made with the supplied ice-making water after the ice within the ice tray is separated and moved to an ice bank, it is possible to reduce a time required for cooling the ice tray to an ice-making temperature. With the help of the above described effects on time saving, it is possible to reduce a total ice-making time required for completing a cycle of ice-making process and also power consumption to be consumed for an ice-making process. In addition, since it is capable of getting the heater in a close contact with the ice tray, it is possible to improve an efficiency of heat transfer.

Further, the ice maker of the present invention is capable of supporting the heater in the lower portion of the ice tray, and thereby it is possible to prevent for the heater from being deviated from the heater housing. Also, by getting the heater in a seal within the heater housing, even if a chilly air is supplied to the ice tray, it is possible to prevent for the chilly air from getting in a contact with the heater. In addition, since the heater is installed in the lower portion of the ice tray, it is possible to easily check the installed state of the heater with the naked eye.

Furthermore, in accordance with the ice maker of the present invention, an overheating sensor for sensing an overheating of the heater is mounting in the ice maker, during coupling a base cover which surrounds the heater installed in the ice tray, and thereby it is possible to reduce a work load required for mounting the overheating sensor.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of an ice maker in accordance with the present invention.

FIG. 2 is an exploded perspective view illustrating a state that an ice tray, a heater and a base cover are mounted on an ice maker in accordance with the present invention.

FIG. 3 is a cross-sectional view of an ice tray in which a heater is installed.

FIG. 4 is a perspective view illustrating an embodiment of a heater.

FIG. 5 is a perspective view illustrating another embodiment of a heater.

FIG. 6 is a cross-sectional view illustrating a buffer portion against a length of a heater formed in an ice tray.

FIGS. 7A, 7B and 7C are views illustrating an example of an ice tray having a heater installed therein, in an ice maker in accordance with an embodiment of the present invention.

FIG. 8 is a cross-sectional view illustrating an example where a heater is accommodated in a heater housing, in an ice maker in accordance with an embodiment of the present invention.

FIG. 9 is a cross-sectional view illustrating another example of an ice tray having a heater that is accommodated in a heater housing, in an ice maker in accordance with an embodiment of the present invention.

FIG. 10 is a perspective view illustrating another example of an ice tray in which a heater of the present invention is installed.

FIG. 11 is a cross-sectional view of the ice tray shown in FIG. 10.

FIGS. 12A, 12B, 12C, 12D and 12E are views illustrating different examples of a support rib of a base cover of the present invention.

FIG. 13 is a side partial cut-away view illustrating an ice maker of the present invention

FIG. 14 is an exploded partial cut-away perspective view illustrating an example where an overheating sensor is installed by an ice tray and a base cover.

FIG. 15 is an exploded partial cut-away perspective view illustrating another example where an overheating sensor is installed by an ice tray and a base cover.

FIG. 16 is an exploded partial cut-away perspective view illustrating another example where an overheating sensor is installed by an ice tray and a base cover.

FIGS. 17A, 17B and 17C are graphs illustrating a comparison of performance of a heater in accordance with an embodiment of the present invention and a heater in accordance with the prior art.

BEST MODE

Hereinafter, embodiments of an ice maker of the present invention will be described with reference to FIGS. 1 through 17. However, these are merely exemplary embodiments and the present invention is not limited thereto.

In the following description, well-known functions and/or constitutions will not be described in detail if they would unnecessarily obscure the features of the present invention. Further, the terms to be described below are defined in consideration of their functions in the embodiments of the present invention and may vary depending on a user's or operator's intention or practice. Accordingly, the definition may be made on a basis of the content throughout the specification.

The technical spirit of the present invention is determined by the claims, and the following embodiments are just means for describing effectively the progressive technical spirit of the present invention to those skilled in the art within the scope of the present invention.

Referring to FIGS. 1 through 3, an ice maker 10 in accordance with the present invention includes an ice tray 20, an ejector 11, a control unit 12, a side guide 13, an ice bank 14, a water supply pipe 15, a water supply cup 16, a full ice lever 17 and a heater 30.

In the ice maker 10, the ice tray 20 has an ice-making space to contain water therein. In the interior of the ice tray 20, a plurality of partition walls are formed so as for the ice-making space to be divided into a plurality of subspaces. Each of the ice-making subspaces divided in the interior of the ice tray 20 may be respectively formed in correspondence with each of ejector pins 11 b, which will be described later.

The ice tray 20 is supplied with water (i.e., ice-making water) through the water supply pipe 15 and the water supply cup 16. The water contained in the ice-making space within the ice tray 20 is then frozen by a chilly air of an ice-making chamber (not shown).

The control unit 12 drives a motor (not shown) to rotate the ejector 11 in the clockwise direction. The ejector 11 includes an ejector shaft 11 a and a plurality of ejector pins 11 b formed spaced apart from each other in the ejector shaft 11 a. When the motor rotates the ejector shaft 11 a in the clockwise direction, the ejector pins 11 b while rotating together with the ejector shaft 11 a in the clockwise direction separates the ice within the ice tray 20 from the ice tray 20 and pushes the ice upwards. The ice pushed upwards by the ejector pins 11 b falls into the ice bank 108 by riding down the side guide 13 formed at one side of the ice tray 20.

As shown in FIG. 3, on the outer circumferential surface of the ice tray 20, at least one heater housing 21 for accommodating the heater 30 is formed. For example, the heater housing 21 may include a pair of protrusions 21 a, 21 b protruded from the outer circumferential surface of the ice tray 20 and a heater accommodating recess 21 c formed the protrusions. However, the heater housing 21 is not limited thereto, and may be formed in a variety of forms other than that can accommodate the heater 30. For example, the heater housing 21 may be formed of only an accommodating recess which is formed by leading on the outer circumferential surface of the ice tray 20 without any separate protrusion.

The heater 30 which is mounted in the heater housing 21 may be a flexible one, as shown in FIG. 4. The heater 30 may include a heating unit 31, a first insulating layer 32 a which is formed so as to surround the heating unit 31, and a second insulating layer 32 b which is formed so as to surround the first insulating layer 32 a.

The heating unit 31 serves to generate heat when a voltage is applied thereto. The heating unit 31 may include one or more hot wire (e.g., a nickel-chromium wire, or copper-nickel wire, etc.). However, the heating unit 31 is not limited thereto, and may be formed in a shape in which a glass fiber is wound on the hot wire, or a shape in which the hot wire is wound on the glass fiber.

Then, the first insulating layer 32 a may be formed by extruding with a silicone or a rubber, and the second insulating layer 32 b may be formed of Ethylene Vinyl Acetate (EVA) or Polyethylene (PE) added with a flame retardant. For example, the second insulating layer 32 b may be formed with a cross-linking treatment by electron beam irradiation. In case where the second insulating layer 32 b is formed with the cross-linking treatment by electron beam irradiation, it is possible to improve the heat resistance of the second insulating layer 32 b and also compensate the brittleness of the second insulating layer 32 b.

For example, in case where the second insulating layer 32 b is formed of PE added with a flame retardant, when irradiating an accelerated electron beams to the second insulating layer 32 b, H ion is dissociated from PE chain to generate radicals. The cross-linking is proceeded by a combination of the radicals. During this process, PE comes to have a reticular structure by the combination of the radicals, and thereby it is possible to improve the heat resistance of the second insulating layer 32 b and also compensate the brittleness of the second insulating layer 32 b. The second insulating layer 32 b may be formed by an extruding process on the first insulating layer 32 a.

Since the heater 30 which may be a flexible type is formed in a shape of a zigzag on the outer circumferential surface of the ice tray 20, the flexible heater 30 is subject to bending in various portions. In this case, each of the bent portions is vulnerable to crack due to continuous stresses and consequently may be damaged. However, the second insulating layer 32 b is treated with the cross-linking treatment by the electron beam irradiation, and thus the heater 30 is already compensated for the brittleness. Even if the heater 30 is installed to be bent, therefore, it is possible to prevent for a crack to occur in the flexible heater 30. In this embodiment, the second insulating layer 32 b is described to be made of EVA or PE treated with the cross-linking by the electron beam irradiation. However, the second insulating layer 32 b is not limited thereto, and may be used with a shrink tube. The shrink tube may be made of a silicone or a rubber elastomer. In this case, the second insulating layer 32 b can be improved in the air-tightness and also is able to withstand the mechanical shock. Further, the shrink tube may be a shrink tube treated with the cross-linking by the electron beam irradiation. In addition, the second insulating layer 32 b may be formed of Cross-Linking Polyethylene (XLPE). XLPE is treated with the cross-linking by a mixture of an organic vulcanized agent and PE to make the structure of PE to the linked state (i.e., cross-linked state) in order to provide the thermosetting and viscoelastic properties to PE.

Referring to FIG. 5, the flexible heater 30 may include a heating unit 31 and an insulating layer 34 surrounding the heating unit 31. The insulating layer 34 may be EVA or PE treated with the cross-linking by the electron beam irradiation. However, the insulating layer 34 is not limited thereto, and may be formed of a XLPE as well.

An example of such type of the heater 30 may be a cord heater, but is not limited thereto.

In case of using the cord heater as the heater 30, the cord heater may be flexible and may be formed with a smaller diameter (e.g., 2˜4 mm) Consequently, when the heater 30 is formed at the outer circumferential surface of the ice tray 20, an area where the heater 30 and the ice tray 20 get in contact each other may be larger. In other words, by forming the heater 30 in a zigzag form on the outer circumferential surface of the ice tray 20, it is possible to improve the area where the heater 30 and the ice tray 20 get in contact each.

In this embodiment, the heater 30 is shown to have a zigzag form on the outer circumferential surface of the ice tray 20, which however is not limited thereto, and additionally may be formed in a variety of forms (e.g., spiral form and the like) in which the heater 30 may be placed compactly on the outer circumferential surface of the ice tray 20. Further, the heater housing 21 is shown to be formed continuously along the heater 30, which however is not limited thereto, and may be formed in a cut-off at regular intervals.

As described above, in case of using the cord heater as the heater 30, the area where the heater 30 gets in a direct contact with the ice tray 20 may become larger, and the heater 30 may be formed over the entire area of the ice tray 20. Therefore, it is possible to reduce the time required for heating the ice tray 20 to a predetermined temperature. In this case, since the overall temperature increasing of the ice-making chamber having the ice maker 10 therein can be reduced, after the ice within the ice tray 20 is ejected to the ice bank 14, when another ice is made again with the supplied ice-making water, it is possible to reduce the time required for cooling the ice tray 20 to the ice-making temperature. Consequently, it is possible to reduce the total time required for completing a cycle of ice-making process, and also to reduce the power consumption required for the ice-making process.

Also, since the heat transfer distance between the heating unit 31 and the ice tray 20 is short (about 1˜2 mm), it is possible to heat the ice tray 20 to the predetermined temperature even with a low power (e.g., 50 Watt), thereby reducing the power consumption required for operating the heater 106 itself

Meanwhile, as shown in FIG. 6, there is formed a heater length buffer 22 in accordance with an error of length of the heater on the end of the heater housing 21. The heater length buffer 22 includes a molding accommodating recess 22 a having a width larger than a heater accommodating recess 21 c, which is formed at the end side of the heater accommodating recess 21, and a molding portion 22 b being inserted into the molding accommodating recess 22 a, which is formed at the connection area of the heater 30 and a lead wire 35.

The molding accommodating recess 22 a may be formed to be extended from the accommodating recess 21 c of the heater housing 21. When the molding portion 22 b is accommodated in the molding accommodating recess 22 a, the molding accommodating recess 22 a may be formed so as for free spaces to exist in the right and left of the molding portion 22 b. In this case, even if the length of the heater 30 is prepared with a little shorter or longer than the reference value, the heater 30 is allowed to be used without any change of design. In other words, the free spaces existing in the right and left of the molding portion 22 b within the molding accommodating recess 22 a may be referred to as a buffer space to supplement any error in the length of the heater 30.

Referring to FIG. 7A showing the heater accommodating recess 21 c of the heater housing 21 formed on the ice tray 20, the bottom surface of the accommodating recess 21 c may be formed in a semi-circular shape, and the both sides of the accommodating recess 21 c may be formed in flat surfaces parallel to each other. Then, the heater 30 which is inserted into the accommodating recess 21 c may be formed in a circular shape. In this case, more than half of the outer circumferential surface of the heater 30 gets in contact with the ice tray 30.

A contact holding member 26 may then be formed between the heater 30 and the inner wall of the heater accommodating recess 21 c. The contact holding member 26 has a role for an empty space or air not to exist between the heater 30 and the inner wall of the heater accommodating recess 21 c. In other words, the contact holding member 26 has a role for the heater 30 to be in a close contact with the inner wall of the heater accommodating recess 21 c. As the contact holding member 26, for example, an adhesive material may be used. Accordingly, the heater 30 may be fixed to the heater accommodating recess 21 c while getting in a close contact with the inner wall of the accommodating recess 21 c. For example, when a thermal conductive adhesive material is used as the contact holding member 21 c, it is possible to increase a thermal conductivity from the heater 30 to the ice tray 20. Further, in the empty space between the heater 30 and the inner wall of the heater accommodating recess 21 c at the lower end of the heater accommodating recess 21 c, a separate sealing member (not shown) may be filled. Accordingly, it is possible for the heater 30 to be fixed within the heater accommodating recess 21 c while reducing the heat loss. The sealing member (not shown) may be formed of the same material as the contact holding member 26.

Referring to FIG. 7B, the cross section of the heater accommodating recess 21 c may be formed in a rectangular shape having an open end, and the insulating layer 34 or the second insulating layer 32 b of the heater 30 may be formed in a rectangular shape corresponding to the heater accommodating recess 21 c. In this configuration, when the heater 30 is inserted into the heater accommodating recess 21 c, about ¾ of the entire outer circumferential surface area of the heater 30 may get in contact with the heater accommodating recess 21 c. Therefore, it is possible to increase the efficiency of heat transfer from the heater 30 to the ice tray 20. Also, the area of the heater 30 to be exposed to the outside is minimized, thereby reducing the heat loss.

Referring to FIG. 7C, the top of the heater accommodating recess 21 c is formed of a semi-circular shape, and the cross section of the heater 30 being inserted into the heater accommodating recess 21 c is formed in a semi-circular shape. In this case, it is possible to expand the area where the heater 30 gets in a contact with the ice tray 20, and also to reduce the area where the heater 30 is exposed to the outside.

Meanwhile, in FIGS. 7A, 7B and 7C, it is described that the heater 30 is fixed to the heater accommodating recess 21 c through the fitting by inserting method. However, the method of fixing the heater 30 to the heater accommodating recess 21 c is not limited thereto. For example, the heater 30 may be fixed to the heater accommodating recess 21 c by using both of the fitting by inserting method and adhering method, and also may be fixed to the heater accommodating recess 21 c using a variety of fixing methods other than those methods.

FIG. 8 is a cross-sectional view illustrating another example where a heater is accommodated in a heater housing, in an ice maker in accordance with an embodiment of the present invention.

Referring to FIG. 8, an additional protrusion 35 may be formed on the outer circumferential surface of the heater 30. In this regard, the additional protrusion 35 may be formed so as to be inclined to the downward direction. When the heater 30 is pressurized to the upper direction after placing at the lower portion of the heater accommodating recess 21 c, since the second insulating layer 32 b or the insulating layer 34 is made of the soft insulating material, the additional protrusion 35 is folded by the inner wall of the heater accommodating recess 21 c, and becomes to be in a close contact with the outer circumferential surface of the heater 30. After the heater 30 is inserted into the heater accommodating recess 21 c, the heater 30 is capable of_being tightly jammed by the additional protrusion 35 within the heater accommodating recess 21 c, and thereby the heater 30 is prevented from getting out from the heater accommodating recess 21 c. In this embodiment, the additional protrusion 35 is shown to be a single, which however is not limited thereto, and may be formed in two or more. In this case, when the heater 30 is inserted into the heater accommodating recess 21 c, the additional protrusion 35 is inserted into a additional protrusion inserting recess (not shown), and thereby the heater 30 is supported by fixing.

In accordance with the present invention, the protrusions 21 a, 21 b protruded on the outer circumferential surface of the ice tray 20 for forming the heater accommodating recess may be formed as a pair of protrusions 21 a, 21 b which are protruded in a horizontal direction on the outer circumferential surface of the ice tray 20, as shown in FIG. 9. In this case, the heater 30 is easily installed in the heater accommodating recess 21 c by the pair of protrusions 21 a, 21 b.

FIGS. 10 and 11 are views illustrating another embodiment of an ice tray, wherein FIG. 10 is a view showing a lower surface of the ice tray, and FIG. 11 is a view showing a cross section of the ice tray.

Referring to FIGS. 10 and 11, the heater housing 21 is formed to be longer than the adjacent protrusion 26 of a pair of protrusions 25, 26 which are protruded from the outer circumferential surface of the ice tray 20 to form a heater accommodating recess. In this case, when the heater 30 is turned off, an area where the chilly air gets in contact with the ice tray 20 becomes wider, and thereby it is possible to improve the radiating effect of the ice tray 20. When describing in more detail, as shown in FIG. 11, a first to an eighth heater accommodating recesses 21 a-1 to 21 a-8 may be formed sequentially from one side of the ice tray 20 to the other side of the ice tray 20. In FIG. 11, eight heater accommodating recesses 21 a-1 to 21 a-8 are shown to be formed on the outer circumferential surface of the ice tray 20, which however is not limited thereto, and may be formed with various numbers other than the above.

Between the pair of the first protrusion 25 and the second protrusion 26 forming a heater accommodating recess respectively at the first to eighth heater housings 21 a-1 to 21 a-8, the first protrusion 25 formed adjacent to one side of the ice tray 20 may be formed with a length corresponding to the diameter of the heater 30 on the outer circumferential surface of the ice tray 20. In this case, when the operator looks the ice tray 20 on one side of the ice tray 30, it is possible to check with the naked eye whether the heater 30 is inserted in close contact within each of the heater housings 21 a-1 to 21 a-8. On the contrary, the second protrusion 26 of the pair of the first protrusion 25 and the second protrusion 26 may be formed with a length longer than that of the first protrusion 25 in the first heater housing 21 a-1, but may be formed not to be higher than the first protrusion 25 forming the adjacent heater housing. For example, the second protrusion 26 of the first heater housing 21 a-1 is formed not to protrude higher than the first protrusion 25 of the second heater housing 21 a-2. In case where the second protrusion 26 of the first heater housing 21 a-1 is formed to protrude higher than the first protrusion 25 of the second heater housing 21 a-2, when the operator looks the ice tray 20 on one side of the ice tray 20, it is difficult to check with naked eye whether the heater 30 is inserted in close contact within the second heater housing 21 a-2.

In case where the heater 30 turns off in operating, the second protrusion 26 has a role of a radiating fin for radiating the heat of the ice tray 20 heated by the heater 30 to the outside. In other words, after ice-separation of the ice within the ice tray 20, the ice tray 20 is ready to produce ice again by being supplied the ice-making water. In this case, in order to cool the ice tray 20 to the ice-making temperature efficiently, the heat of the ice tray 20 provided by the heater 30 must be quickly released to the outside. In consideration of the above reason, the second protrusion 26 is formed with a length longer than that of the first protrusion 25 in order to expand the area where the ice tray 20 gets in contact with the chilly air, and thereby it is possible to cool rapidly the ice tray 20 to the ice-making temperature. As described above, the second protrusion 26 has a role of the radiating fin as well.

As shown in FIGS. 1, 2 and 12, the ice maker 10 in accordance with the present invention may further include a base cover 40 provided on the lower portion of the ice tray thereof.

The base cover 40 is coupled to the ice tray 20 so as to surround the lower part of the ice tray 20. The base cover 40 includes support ribs 41 which support the heater 30 being inserted into the heater housing 21 c of the heater supporting portion 21 formed at the lower portion of the ice tray 20. The support ribs 41 may be formed on the inner surface of the base cover 40 corresponding to the heater accommodating recess 12 c. The support ribs 41 may has a role of the cover covering the end of the heater accommodating recess 21 c. A plurality of through holes 42 are formed in the base cover 40 through which the chilly air is transferred to the ice tray 20 preferably without any interference. It is also preferred that a space between each of the support ribs 41 becomes a pathway of transfer for the chilly air. In addition, a shield 43 may be formed in the terminal of each of the support ribs 41. The shield 43 may be formed to be extended from side to side at the terminal of the support rib 41. In this regard, the shield 147 may be formed while closing the inlet of the heater accommodation recess 21 c. Then, the heater accommodating recess 21 c having the heater 30 therein becomes the state that is shielded from the outside. In this description, the shield 43 is described as being formed to be extended from side to side at the terminal of the support rib 41, which however is not limited thereto, and may be formed separately from the support rib 41 and coupled at the terminal of the support rib 41.

FIGS. 12A, 12B, 12C, 12D and 12E are different examples of a support rib to be installed in a base cover, in accordance with another embodiment of the present invention.

Referring to FIG. 12A, a shield is not formed at the terminal of the support rib 41, but may be formed by contacting with the heater 30 to be installed in the heater accommodating recess 21 c. According to the configuration, the support rib 41 becomes to support the heater 30, and thereby the heater 30 can be prevented from getting off from the heater accommodating recess 21 c.

Referring to FIG. 12B, the width of the shield 43 formed at the terminal of the support rib 41 is formed with the substantially same width as the heater accommodating recess, and supports the heater 30 in the state of being inserted into the heater accommodating recess 21 c. According to the configuration, the shield 43 may shield the heater 30 from the outside while supporting the heater 30.

Referring to FIG. 12 c, the shield 43 formed at the terminal of the support rib 41 may be formed while closing the inlet of the heater accommodating recess 21 c. On the upper surface side of the shield 43, a heater support protrusion 43 a being in contact with the heater 30 may be formed. According to the configuration, the area where the shield 43 gets in a contact with the heater 30 is reduced, and thereby the shield 43 and the support rib 41 can be prevented from being deformed.

In other words, in case where the base cover 40 and the support rib 41 are made of a synthetic resin respectively, when the shield 43 gets in a contact with the heater 30, it may result in deformation in the shield 43 and the support rib 41 due to the heat generated by the heater. In this case, the heater support protrusion 43 a is formed on the upper surface of the shield 43 in order to reduce the area where the shield 43 gets in a contact with the heater 30, and thereby it is possible to reduce a heat transfer from the heater 30 to the shield 43. Accordingly, the shield 43 and the support rib 41 can be prevented from being deformed due to the heater 30.

The shield 43 formed at an end of the support rib 41 may be formed with a width same as the width between the first protrusion 25 and the second protrusion 26 forming the heater accommodating recess and the outer edge, as shown in FIG. 12D, or may be formed so as to surround the first protrusion 25 and the second protrusion 26 forming the heater accommodating recess, as shown in FIG. 12E.

In addition, a sealing member (not shown) may be filled in the empty space between the inner wall of the heater accommodating recess 21 c and the heater 30 within the heater accommodating recess 21 c. In this case, it is possible to seal the heater 30 within the heater accommodating recess 21 c to reduce the heat loss. Further, the sealing member (not shown) has a role of a kind of buffer, and thereby the shield 43 and the support rib 41 can be prevented from being deformed due to the heat generated by the heater 30.

On the other hand, as shown in FIGS. 2, 13, 14 and 15, a first overheating sensor 51 and a second overheating sensor 52 may be installed in the first lead wire 36 and the second lead wire 37 connected to both ends of the heater, respectively. The overheating sensors may be formed in one side of the first lead wire and the second lead wire as well.

The first lead wire 36 and the second lead wire 37 are connected to the terminal of a main board 50 installed in a control box 12. The first overheating sensor 51 and the second overheating sensor 52 serve to prevent the heater 30 from being overheated. For example, the first overheating sensor 51 and the second overheating sensor 52 may detect whether the temperature of the heater 30 exceeds a predetermined threshold temperature in order to prevent the heater 30 from being overheated. It is, however, not limited thereto, and the first overheating sensor 51 and the second overheating sensor 52 may detect whether an overcurrent flows through the heater 30 in order to prevent the heater 30 from being overheated.

In addition, there is provided a sensor support unit 60 in one side of the base cover 40. The sensor support unit 60 includes a support member 63 in which coupling portions 61, 62 are formed. The coupling portions 61, 62 are extended between the control box 12 and the ice tray 20 and are connected to the first overheating sensor 51 and the second overheating sensor 52. It is preferred that the support member 63 of the sensor support unit 60 is placed between the control box 12 and the ice tray 20 so as for an interference not to occur upon coupling the base cover 40 and the ice tray 20 each other. The coupling portions 61, 62 may have an inserting recess formed on the side of the support member 63 so as for the first overheating sensor 51 and the second overheating sensor 52 to be coupled. As described above, the first overheating sensor 51 and the second overheating sensor 52 may be coupled by being inserted into the inserting recess forming the coupling portions 61, 62, which however is not limited thereto, and may be coupled by a variety of methods other than the above.

In this embodiment, the support member 63 is shown in a way that the coupling portions 61, 62 are formed integrally with the base cover 40. However, this is not limited thereto, and the support member 63 may be manufactured separately from the base cover 40 and then may be coupled to the base cover 40. The first overheating sensor 51 and the second overheating sensor 52 may get in contacts with the ice tray 20 while being supported by the coupling portions 61, 62.

In addition, the support member 63 may have a first inserting hole 64 formed therein. When the first overheating sensor 51 and the second overheating sensor 52 are inserted through the first inserting hole 64, the first inserting hole 64 is coupled to each of the coupling portions 61, 62. Then, the first lead wire 36 and the second lead wire 37 are drawn out through the first inserting hole 64 and are respectively connected to the terminal of the main board 50. As shown in FIG. 15, the first inserting hole 64 may have a second inserting hole 65 formed in the lower portion thereof. Accordingly, the lead wires to be connected to the first overheating sensor 51 or the second overheating sensor 52 may be inserted separately. In the side of the control box of the support member 63, a molding housing 66 to which the molding portion 22 b of the heater is fixed may be formed. In the molding housing 66, the molding portion 22 b may be fixed. When the molding portion 22 b is accommodated in the molding housing 66, the molding housing 66 may be formed so as for free spaces to exist in the left and right or in the top and bottom of the molding portion 22 b. In this case, even if the length of the heater 30 is manufactured in a slightly shorter or longer than the reference value, it is possible to use the heater 30 without any change of design. In other words, the free spaces which exist in the right and left or in the top or bottom of the molding portion may be referred to as a buffer space supplementing an error in length of the heater. In this case, in the side of the control box 12 corresponding to the molding housing 66, a lead-in portion is formed so as for the molding housing 66 to be inserted.

On the other hand, as shown in FIG. 16, the support member 63 may have a though hole 65 which is communicated with the coupling portions 61, 62 formed therein so as for the first overheating sensor 51 and the second overheating sensor 52 to be inserted respectively. The through hole 65 is allowed for the first overheating sensor 51 and the second overheating sensor 52 to be inserted respectively in a state that the base cover 40 and the ice tray 20 are coupled each other.

In accordance with an embodiment of the present invention, since the first overheating sensor 51 and the second overheating sensor 52 are coupled to the coupling portions 61, 62 formed in the support member 63 of the base cover 40, it is possible to fix stably the first overheating sensor 51 and the second overheating sensor 52. Also, the task of fixing the first overheating sensor 51 and the second overheating sensor 52 comes to be easy, and the first lead wire 36 and the second lead wire 37 can be clearly arranged.

Further, since the control box 12 pressurizes the support member 63 when being coupled to the ice tray 20, the first overheating sensor 51 and the second overheating sensor 52 maintain close contacts with the ice tray 20, and thereby it is possible to accurately detect whether the heater 30 gets overheating. In other words, the first overheating sensor 51 and the second overheating sensor 52 are primarily brought into close contacts with the ice tray 20 by the base cover 40, and are secondarily brought into further close contacts with the ice tray 20 by the control box 12.

FIGS. 17A, 17B and 17C are graphs illustrating a comparison of performance of a heater in accordance with an embodiment of the present invention and a heater in accordance with the prior art.

Referring to FIG. 17A, it can be seen that the heater 30 in accordance with an embodiment of the present invention takes a first time (t1) to heat the ice tray 20 to the predetermined temperature, and on the contrary, the heater in accordance with the prior art takes a second time (t2) longer than the first time (t1) to heat the ice tray 20 to the predetermined temperature. This is contributed that by forming the heater 30 in the form of a cord heater, the area where the heater 30 gets in a direct contact with the ice tray 20 is widened, and by forming the heater 30 over the entire area of the ice tray 20, the entire area of the ice tray 20 is heated uniformly. In addition, this is contributed that the chilly air is shielded not to get in contact with the heater 30 by the shield.

Referring to FIG. 17B, it can be seen that the power required for the heater 30 in accordance with an embodiment of the present invention is lower than the power required for the heater in accordance with the prior art. This is contributed that the heater 30 in accordance with an embodiment of the present invention has a relatively shorter distance of heat transfer, and thereby it is possible to heat the ice tray 20 to the predetermined temperature even at a low power.

Referring to FIG. 17C, it can be seen that in case of using the heater 30 in accordance with an embodiment of the present invention, the temperature of the ice-making chamber is gradually increased with the not high temperature increase, but in case of using the heater in accordance with the prior art, the ice-making chamber is rapidly increased with the high temperature increase. This is contributed that as shown in FIGS. 17A and 17B, the heater 30 in accordance with an embodiment of the present invention is capable of heating the ice tray 20 to the predetermined temperature in a short time even using a low power.

While the embodiments of the present disclosure have been illustrated and described as described above, it will be appreciated by those skilled in the art that various modifications, additions and substitutions to the embodiments are possible, without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure is not limited to the described embodiments, but should be defined by the accompanying claims and equivalents thereof. 

1. An ice maker, comprising: an ice tray; at least one heater housing formed in the ice tray; at least one heater to heat the ice tray, the heater including an outer shell so as to be accommodated in a close contact within the heater housing; and a base cover coupled to the ice tray, the base cover including support ribs for pressurizing the heater mounted in the heater housing to make the heater getting in a close contact with the heater housing.
 2. The ice maker of claim 1, wherein the heater is a cord heater.
 3. (canceled)
 4. (canceled)
 5. (canceled)
 6. (canceled)
 7. (canceled)
 8. (canceled)
 9. (canceled)
 10. The ice maker of claim 1, wherein each of the support ribs further includes a shield which is formed at the terminal of the support rib to shield the inside of the heater housing.
 11. The ice maker of claim 10, wherein the heater support is formed by protruding from the shield, the heater support further comprising a heater support protrusion which gets in a contact with the heater.
 12. (canceled)
 13. The ice maker of claim 10, wherein the heater housing comprises: a pair of protrusions which are formed by protruding from the outer circumferential surface of the ice tray; and an accommodating recess which is formed between the pair of protrusions and allows the heater to be inserted, wherein the shield is formed at the terminal of the support rib and gets in contact with the pair of protrusions to radiate the heat transferred from the heater through the pair of protrusions.
 14. The ice maker of claim 1, further comprising a sealing member which is filled within the heater accommodating recess to support the heater, the heater accommodating recess composing the heater housing.
 15. The ice maker of claim 1, wherein the heater housing comprises: a pair of protrusions formed by protruding from the outer circumferential surface of the ice tray, any one of the pair of protrusions being protruded with a length longer than that of the other protrusion.
 16. The ice maker of claim 15, wherein the heater housing is formed in plurality on the outer circumferential surface of the ice tray having a semi-cylindrical shape, and wherein a first protrusion of the pair of protrusions adjacent to one side or the other side of the ice tray is protruded with a length corresponding to a diameter of the heater, and a second protrusion of the pair of protrusions is protruded with a length longer than that of the first protrusion.
 17. The ice maker of claim 16, wherein the second protrusion of the pair of protrusions is formed by protruding with a length less than that of the first protrusion of the pair of protrusions of the adjacent heater housing.
 18. An ice maker, comprising: an ice tray; at least one heater housing formed in the ice tray; at least one heater to heat the ice tray, the heater including an outer shell so as to be accommodated in a close contact within the heater housing; an overheating sensor for detecting whether the heater is overheated, one side of the overheating sensor being installed on a lead wire connected to the heater; a base cover coupled to the ice tray to protect the heater; and a sensor support unit provided in one side of the base cover, the sensor support unit comprising a support member in which a coupling portion is formed to be extended to the side surface of the ice tray so as for the overheating sensor to get in a close contact with the ice tray, wherein the base cover comprises support ribs formed therein, the support ribs pressurizing the heater mounted in the heater housing to make the heater in a close contact with the heater housing.
 19. The ice maker of claim 18, wherein the support member gets in a close contact with the ice tray and is positioned between the ice tray and a control box coupled to the ice tray.
 20. The ice maker of claim 18, where the support member with the coupling portion therein comprises at least one inserting hole formed therein through which a lead wire passes.
 21. The ice maker of claim 18, wherein the coupling portion of the support member includes an inserting recess formed on the surface opposing to the ice tray in the extended frame, and wherein the overheating sensor is inserted into the inserting recess to get in a close contact with the ice tray.
 22. The ice maker of claim 21, wherein the support member includes a through hole communicating with the coupling portion formed thereon, so that the overheating sensor gets in a close contact with the ice tray which is inserted into the coupling portion through the through hole.
 23. The ice maker of claim 18, wherein the heater is a flexible heater, the heater including a molding portion which is formed on the area of connection between the heater and the lead wire, and wherein a molding housing is formed in the support member, the molding housing accommodating the molding portion.
 24. (canceled)
 25. An ice maker, comprising: an ice tray; at least one heater housing formed in the ice tray; and at least one heater to heat the ice tray, the heater being including an outer shell so as to be accommodated in a close contact within the heater housing, wherein the heater comprises: a heating unit; a first insulating layer formed by surrounding the heating unit, the first insulating layer being made of a soft or an elastic material; and a second insulating layer formed by surrounding the first insulating layer, the second insulating layer being treated with a cross-linking treatment.
 26. (canceled)
 27. The ice maker of claim 25, wherein the second insulating layer is formed by an extruding process on the outer circumferential surface of the first insulating layer.
 28. The ice maker of claim 25, wherein the second insulating layer is made of Ethylene Vinyl Acetate (EVA) or Polyethylene (PE) treated with the cross-linking treatment by an electron beam irradiation.
 29. The ice maker of claim 25, wherein the second insulating layer is made of EVA or PE added with a flame retardant and treated with the cross-linking treatment by the electron beam irradiation.
 30. The ice maker of claim 25, wherein the second insulating layer is a shrink tube treated with the cross-linking treatment by the electron beam irradiation.
 31. The ice maker of claim 26, the second insulating layer is made of Cross Linking Polyethylene (XLPE).
 32. (canceled)
 33. (canceled)
 34. (canceled) 